Feeder tap



March 28, 1961 GENTER 2,977,441

FEEDER TAP Filed Jan. 26, 1959 INVENTOR.

ALBERT H. GEN r52 H15 A TTOENE Y United States Patent FEEDER TAP Albert H. Genter, 769 Larchmont Road, Mount Lebanon 16, Pa.

Filed Jan. 26, 1959, Ser. No. 789,141

8 Claims. (Cl. ZOO-115.5)

This invention relates generally to trolley wire feeder taps and more particularly to a fused trolley wire feeder tap having a readily replaceable fuse.

The principle of this invention is the provision of a fused trolley wire feeder tap having its hook or bare wire connection end open to permit free egress of pres sure built up by the blowing of a fuse.

Another object is the provision of a fused trolley wire feeder tap having a bayonet type latch to retain the fuse in assembled relation against spring pressure.

Another object is the provision of a support for a shield on the power cable terminal which substantially fills the bore of the insulated tubular sleeve of the trolley wire feeder tap to prevent blowback of the gas pressure developed when a fuse blows within the tap.

Another object is the provision of a frusto conical seat in the terminal of a fused trolley wire feeder tap having the cartridge fuse mounted under spring pressure to increase the electrical contact between the fuse and the terminal.

Another object is the provision of cartridge type fuse having frusto conical ferrules at the ends thereof for mounting the same under compression toincrease the electrical conductivity to the ferrules of the fuse.

Another object is the provision of a simplified form of fused trolley wire feeder tap that is open to the atmosphere in the direction opposite to that of the hand grip to prevent burning from blowback.

Another object of this invention is the provision of a simplified structure of a fused trolley wire feeder tap that may be open and closed without the aid of tools for the purpose of changing the fuse therein.

Other objects and advantages appear in the following description and claims.

The accompanying drawings show for the purpose of exemplification without limiting the claims thereto, certain practical embodiments of the invention wherein:

Fig. 1 is a view in vertical section of a trolley wire feeder tap with all the parts shown in assembled relation.

Fig. 2 is a sectional view taken on the line 2-2 of Fig. 1.

Fig. 3 is a sectional view showing a modified form of the fuse and terminals employed in the trolley wire feeder tap.

Referring to the'drawing the trolley wire feeder tap has an outer tubular sleeve 1 preferably made of a synthetic material that is impervious to liquids and has very good electrical insulating qualities and is mechanically strong. The tube 1 is provided at one end with the annular shield 2 made of the same material which is in the form of a washer pressed on the end of the sleeve and secured in position.

The opposite or handle end of the sleeve has mounted on the interior thereof a pair of spaced abutments illustrated at 3 and 4. These abutments are heavy washers preferably made of the same material as that of the tube but of considerably greater wall thickness. Each of these ice abutment washers 3 and 4 are secured in place by the pins 5 which are also preferably made of the same material as the abutments in the tube 1.

Each of the abutments 3 and 4 are provided with the bore 6 which will readily pass the insulated power cable 7 but it is preferable not to provide an excessive clearance between the power cable and the abutments 3 and 4 so as to provide a choking effect on any gas pressure developed within the tubular sleeve when the fuse explodes due to an overload imposed thereon.

As shown in Fig. 1, the conductor 8 of the insulated power cable 7 is bared so that it passes through the eye 10 at the lower end of the stem 11 on the terminal 12.

The lower end of the stem 11 is threaded to receive the internally threaded ferrule 13, the lower end of the bore of which may be beveled to provide a conical mouth to receive the end of the bared cable 8 and lock it firmly in the eye 10 and thereby provide a good electrical connection therebetween.

The terminal 12 has an enlarged head 14 forming the under shoulder 15 on which is seated the washer 16.

The perimeter of the washer has a close sliding fit with the bore of the tube 1.

A spring 17 is seated under the washer 16 and against the washer surface of the abutment 3. Thus the spring 17 applies pressure to the underside of the head 14 of the terminal 12 forcing it away from the abutment 3.

The head 14 of the terminal 12 together with the washer 16 functions as a restriction to the flow of fluid under pressure when the fuse bursts upon being overloaded. The pressure therein forces the washer 16 towards the abutment 3 further compressing the spring 17 but restricting the flow of gases from the chamber 18 downwardly towards the abutment 3. However, since the bore 6 in the abutment 3 does not provide material clearance the gases are again restricted by this abutment and they are then caused to expand in the second chamber 19 after which they would be required to pass through the bore 6 of the abutment 4 before reaching the atmosphere or the lower end of the power cables 7. Thus the structure disclosed herein provides three restricted paths that the gases must negotiate before escaping to the atmosphere and intermediate of these three restrictions an expansion chamber is provided.

In view of the fact that the opposite end of the tube has considerable clearance for the passage of gas substantially no gas reaches the lower end of the tubular sleeve.

The fuse 20 is provided with the end ferrules 21 the lower one being seated in the socket 22 of the terminal 12 which socket may be slit vertically as indicated by the dotted lines 23 so as to provide a clamping action on the ferrule 21 of the fuse for the purpose of providing a good electrical contact therebetween.

The opposite end of the fuse is seated in a similar terminal socket 24 of the terminal member 25. The socket 24 is likewise slotted as indicated at 23 to tightly grasp the ferrule 21 at the upper end of the fuse 20.

The opposite end of the terminal 25 is provided with a threaded opening 26 for receiving the threaded end of the bare wire connector which in this case is in the form of a hook 27 that may be placed over a bare trolley wire for the purpose of supplying electrical energy to the power cable 7 through the fuse 20. The stem of the bare wire connector 27 may be of any desirable length suitable for the conditions under which the fused feeder tap is used.

The bore of the tube 1 is threaded at its upper end as indicated at 28 to receive the ferrule 30, the exterior of which is threaded to be received in the upper end of the tube 1 and become secured thereto by means of a locking'thread formation or pin or other suitable device.

Thus the ferrule 30 is secured relative to the tube 1.

The bore 31 of the ferrule is considerably larger than the diameter of the terminal 25 so as to provide a large clearance 32 therebetween for readily discharging any gas under pressure developed within the chamber 18 of the tubular sleeve 1 due to the explosion created by' the fuse when subjected to currents much greater than its capacity. Thus since the chamber 18 has one end substantially open the gas pressure developed therein has substantially free exit which will prevent the tubular sleeve 1 from exploding and blowing apart.

The terminal 25 is provided with the locking pin 33 which is in the form of the bayonet pin that fits in the sockets 34 of the ferrule 30 when in position shown in Fig. 1. However, at a position at right angle to the sockets 3d the ferrule 3t) is provided with the slots 35 positioned diagonally across from one another as shown in Fig. 2 thereby providing considerably greater area in the passage from the chamber 18 to the exterior of the tubular sleeve. One end of the locking pin 33 could be employed to hold the fuse in assembled relation, however, it is preferred to have the pin extend on opposite sides of the terminal 25 so as to provide a uniform application of pressure on the fuse it Again the long pin 33 providing two points for the application of pressure aids in properly aligning the terminal 25 in the enlarged bore 32 of the ferrule 30 and thus provide a uniform distribution of the escape path for the gases is suin therefrom.

The hook 27 on the bare wire connector provides a convenient mode for grasping by the hand to compress the spring 17 and thereby release the pin 33 from the sockets 34 to enable the operator to rotate the terminal 25 and thus align the locking pin 33 with the slots 35 to permit the withdrawal of the terminal 25 and the pin 33 from the chamber 18 for replacing the fuse 26.

When the terminal 25 has been removed from the bore of the tubular sleeve 1 one may move the insulated conductor 7 upwardly through the bores of the abutments 3 and 4 so that the upper end of the terminal 12 eX tends out through the bore 32 of the ferrule 30 for the purpose of cleaning the same and replenishing the fuse 20.

The terminals 12 and 25 as shown in Fig. 3 are provided with the sockets having a cylindrical portion 35 g and the tapered portion 37 to receive the correspondingly shaped ferrule on the ends of the fuse 33. The

bottoms of the sockets areflat as indicated at 39 to permit the use of a fuse having ferrules smaller than the tapered portion 37. Since the pressureof the spring 17 is partially compressed when the locking pin 33 is set in the bayonet sockets 34, the pressure exerted by the spring is continuously maintained between the frusto conieal portions 317 of the sockets and complementary frusto conical ferrules. Thus the taper of these frusto conical parts aids in providing a more secure electrical eonnection between the members. The ferrules 21 may be constructed to fit against the flat bottom 39 and the adjacent cylindrical. portion of the socket 24 shown in Fig. 3.

lclairn: i

l. A trolley wire feeder tap comprising a tubular sleeve of electrical insulating material, an abutment in the bore of said tubular sleeve adjacent one end leaving a re stricted openinvsufficiently large through which to draw an insulated power cable, a second abutment in the bore of said tubular sleeve inwardly of said first abutment to form a chamber between said abutments, said second abutment having a restricted opening sufliciently large to pass the insulated power cable, a first terminal having on one end an electrical connection for a power cable and having on its other end a fuse socket, a spring between said terminal and said second abutment, a secend terminal having a large blowout clearance with the bore of the other end. of said tubular sleeve, a fuse socket in one end of said second terminal to receive the other end of a fuse extending between said terminals, a bare wire connector on said second terminal, and latch means to hold said second terminal in said tubular sleeve and to apply pressure through the fuse and compress said spring to hold said fuse in assembled relation.

2. A trolley wire feeder tap comprising a tubular sleeve of electrical insulating material, an abutment in the bore of said tubular sleeve adjacent one end leaving an opensufliciently large through which to draw an insulated power cable, a first terminal having on one end an electrical connection for a power cable and having on its other end a fuse socket, a spring between said terminal and said abutment, a second terminal having a large blowout clearance with the bore of the other end of said tubular sleeve, a fuse socket in one end of said second terminal to receive the other end of a fuse extending between said terminals, a bare wire connector on said second terminal and latch means to hold said second terminal in said tubular sleeve and to apply pressure through the fuse and compress said spring .to hold said fuse in assembled relation, said latch means includes a shoulder and a slot in the bore of said sleeve and a pin on said second terminal to slide through said slot and engage on said shoulder to form a bayonet type locking pm.

3. A trolley wire feeder tap comprising a tubular sleeve of electrical insulating material, an abutment in the bore of said tubular sleeve adjacent one end leaving an open ing sufficiently large through which to draw an insulated power cable, a first terminal having on one end an electrical connection for a power cable and having on its other end a fuse socket, a spring between sai terminal and said abutment, a second terminal having a large blowout clearance with the bore of the other end of said tubular sleeve, a fuse socket in one end of said sec-- end terminal to receive, the other end of a fuse extending between said terminals, a bare wireconnector on said second terminal, latch means to hold said second terminal in said tubular sleeve and to apply pressure through the fuse and compress said spring to hold said fuse in assembled relation, and a shoulder on said first terminal, and a washer under said shoulder and substantially filling the bore of said tubular sleeve to prevent back pressure along said cable.

4. A trolley wire feeder tap comprising a tubular sleeve of electrical insulating material, an abutment in the bore of said tubular sleeve adjacent one end leaving an opening sufliciently large through which to draw an insulated power cable, a first terminal having on one end an electrical connection for a power cable and having on its other end a fuse socket, a spring between said terminal and said abutment, a second terminal having a large blowout clearance with the bore of the otherend of said tubular sleeve, a fuse socket in one end of said second terminal to receive the other end of a fuse extending between said terminals, a bare wire connector on said second terminal, latch means to hold said second terminal in said tubular sleeve and to apply pressure through the fuse and compress said spring to hold said fuse in assembled relation, and passages forming three restrictions for the flow of gas under pressure at the power cable end ofthe trolley wire feeder tap as opposed to large blowout clearance at the opposite end of the feeder tap.

5. A trolley wire feeder tap comprising a tubular sleeve of electrical insulating material, an abutment in the bore at one end of said sleeve leaving a restricted opening to tightly embrace a power cable connection, a terminal having on one end an electrical connection for a power cable and having on its other end a fuse socket, a spring between said terminal and said abutment, a shoulder in the bore at the other end of said sleeve with an open slot adjacentithereto, a second terminal materially smaller than said shoulder to pass the same when inserted in the bore of said sleeve, a fuse socket in one end of said second terminal, a pin projectingfrom said second terminal to pass through said slot and catch on said shoulder as a bayonet lock when said second terminal is turned to place said pin at an angle relative to said slot but leaving a large blowout clearance with said bore and shoulder and including said slot, and a bare conductor on said second terminal to engage a trolley wire.

6. A trolley wire feeder tap comprising a tubular sleeve of electrical insulating material, an abutment in the bore at one end of said sleeve leaving a restricted opening to tightly embrace a power cable connection, a terminal having on one end an electrical connection for a power cable and having on its other end a fuse socket, a spring between said terminal and said abutment, a shoulder in the bore at the other end of said sleeve with an open slot adjacent thereto, a second terminal materially smaller than said shoulder to pass the same when inserted in the bore of said sleeve, a fuse socket in one end of said second terminal, a pin on said terminal to pass through said slot and catch on said shoulder when said second terminal is turned but leaving a large blowout clearance with said bore and shoulder and including said slot, a bare conductor on said second terminal to engage a trolley wire, and an annular flange carried by said first terminal and slidable on the inner surface of the bore of said sleeve to form an expansion chamber between said flange and said abutment.

7. A trolley wire feeder tap comprising a tubular sleeve of electrical insulating material, an abutment in the bore 30 at one end of said sleeve leaving a restricted opening to tightly embrace a power cable connection, a terminal having on one end an electrical connection for a power cable and having on its other end a fuse socket, a spring between said terminal and said abutment, a shoulder in the bore at the other end of said sleeve with an open slot adjacent thereto, a second terminal materially smaller than said shoulder to pass the same when inserted in the bore of said sleeve, a fuse socket in one end of said second terminal, a pin on said terminal to pass through said slot and catch on said shoulder when said second terminal is turned but leaving a large blowout clearance with said bore and shoulder and including said slot, a bare conductor on said second terminal to engage a trolley wire, and a second abutment spaced from said first abutment and having a restricted opening to tightly embrace a power cable connection, said first and second abutments providing an expansion chamber therebetween.

8. The trolley wire feeder tap of claim 7 characterized by an annular flange carried by said first terminal and slidable on the inner surface of the bore of said sleeve and spaced from said first abutment to form with said second abutment a second expansion chamber in tandem with said first expansion chamber.

References Cited in the file of this patent UNITED STATES PATENTS 

